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131.
Hanane Fathi SeongHan Shin Kazukuni Kobara Hideki Imai 《Wireless Personal Communications》2010,54(1):225-236
To avoid the risk of long-term storage of secrets on a portable device, an online credential system supports the roaming user
in retrieving securely at various locations his private key and other material to generate anonymous signatures. The protocol
proposed here allows a roaming mobile user to access anonymously services such as whistle blowing and net-counselling. Our
approach: (1) allows a mobile user, remembering a short password, to anonymously and securely retrieve the credentials necessary
for his anonymous communication without assuming a pre-established anonymous channel to the credential server or establishing
an anonymous channel using the time-consuming existing rerouting techniques; (2) provides authenticated anonymous access to
privacy-related services without rerouting the packets; (3) helps combatting the abuse of anonymity for performing illegal
activities (e.g. redistribution of copy-righted contents, illegal drug trading and so on). 相似文献
132.
The urban heat island mitigation effect of conversion from asphalt-covered parking areas to grass-covered ones is estimated by observation and calculation. The mean surface temperature in a parking lot is calculated from a thermal image captured by an infrared camera. The sensible heat flux in each parking space is calculated based on the surface heat budget. The reduction in the sensible heat flux is estimated to be approximately 100-150 W m−2 during the day and approximately 50 W m−2 during the night, in comparison with an asphalt surface. The air temperature reduction by the spread of grass-covered parking areas is calculated to be about 0.1 °C. Furthermore, consideration is given to the appearance of the parking lot, the growth of grass, the effects of the weight of a car and the heat radiated from its engine, the costs of construction and maintenance, etc. 相似文献
133.
Misao Kimura Hideki Hayashi Toshiyuki Kajihara Masakazu Kato Katsuhiko Kouchi 《Electrical Engineering in Japan》2008,165(4):11-20
Advanced energy storage systems have been widely applied to industries and are being installed at large buildings and factories to realize efficient energy usage. This paper presents a control method involving load frequency control and distribution network control (loss reduction control) using a part of customers' owned battery capacity. When 10% of total battery capacity of 100 MW in a network of 30‐GW generator capacities is used for load frequency control, a total of 1500‐MW generation units for load frequency control, at maximum, can be stopped without deterioration of power quality. In addition, when batteries are used for loss reduction in a distribution network, 2% of the loss on a summer day can be reduced. To realize both effects to their fullest, a novel integrated control algorithm is proposed and its economic effect is evaluated by numerical simulations. © 2008 Wiley Periodicals, Inc. Electr Eng Jpn, 165(4): 11–20, 2008; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20704 相似文献
134.
Tetsuji Nishikawa Naoki Sakamoto Hideki Ueno Hiroshi Nakayama 《Electrical Engineering in Japan》2004,146(2):27-36
Discharge characteristics have been investigated for a needle–plane electrode configuration containing insulating barriers with a narrow gap which has been placed between the needle and the plane. The characteristics of creeping discharge developed in the narrow gap of the barrier filled with SF6 are especially considered. In the case of a configuration with a backside electrode below the needle, the corona generated from the needle easily extended to the gap. On the other hand, for a configuration without a backside electrode, the corona has hardly extended to the gap, and on increasing the applied voltage the corona developed greatly in the gap. This difference in corona extension should affect the flashover characteristics in the present system. © 2003 Wiley Periodicals, Inc. Electr Eng Jpn, 146(2): 27–36, 2004; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.10248 相似文献
135.
Hideki Murayama Shigeki Tomonoh J. Michael Alford Michael E. Karpuk 《Fullerenes, Nanotubes and Carbon Nanostructures》2005,12(1):1-9
In the last decade, application of fullerenes has been proposed actively in a wide range of areas, and recent developments suggest that many of those applications are to be practical technologies. However, there has been no large-scale production enterprise for commercial usage of fullerenes. High production cost and limited availability of fullerenes have been the main obstacle in the development of the Fullerene Market. Improved flame-based technology leads to the most feasible process for mass production of fullerenes, since it is a continuous process and uses inexpensive hydrocarbons as its starting materials. In May 2003, we started fullerene production in tons and more to supply fullerenes with reasonable price as practical materials for industries. 相似文献
136.
Hideki Hyuga Mark I. Jones Kiyoshi Hirao Yukihiko Yamauchi 《Journal of the American Ceramic Society》2004,87(5):894-899
Si3 N4 /carbon fiber composites have been produced with and without seeding by an extrusion and sintering process. In both cases the carbon fibers were aligned along the direction of extrusion, but the Si3 N4 grains were only aligned in the seeded material. The mechanical properties of the specimens showed anisotropy with respect to the grain alignment, with both strength and toughness being highest in the direction parallel to the extruding direction. In this direction the seeded specimen, where both the Si3 N4 grains and the carbon fibers were aligned, showed both higher fracture toughness and higher fracture strength than the nonseeded specimen where only the fibers were aligned. 相似文献
137.
Sanae Shimizu Kazuhiko Yamamoto Caihau Wang Yutaka Satoh Hideki Tanahashi Yoshinori Niwa 《Electrical Engineering in Japan》2005,152(3):29-38
Moving object detection with a mobile image sensor is an important task in robotics and computer vision, when considering the practical use of robotics in human environments. In this paper, we propose a robust method that detects moving objects in the environment using the omnidirectional depth information obtained by a mobile Stereo Omnidirectional System (SOS). In order to detect only the moving objects within the depth image that are obtained by a sensor in motion, we first estimate the ego‐motion of the sensor, and generate a predicted depth image for the current time from the depth obtained at the previous time by only considering the ego‐motion of the sensor. Then the predicted depth image is compared with the actual one obtained at the current time, and the inconsistent regions are detected as moving objects. When the sensor moves, occlusions will occur in the scene and they will cause false detections. However, these false detections can be suppressed by estimating the occlusion regions using the ego‐motion parameters of the sensor and the jump edges in the depth image. The effectiveness of the method is shown with experimental results for a real environment. © 2005 Wiley Periodicals, Inc. Electr Eng Jpn, 152(3): 29–38, 2005; Published online in Wiley InterScience ( www.interscience. wiley.com ). DOI 10.1002/eej.20155 相似文献
138.
139.
Changes in triacylglycerols (TAG) and phospholipids (PL) compositions of cooked Japanese sardine meats as such or with prior addition of ethylene diaminetetracetic acid (EDTA) or a combination of nitrite and ascorbate were evaluated during chilled storage using gas chromatography and selected ion monitoring gas chromatography/mass spectrometry. The TAG molecular species compositions remained unchanged, while certain species of PL molecular species changed during storage at 2 °C for 14 days. The PL containing polyunsaturated fatty acids were highly susceptible to autoxidation. The PL fractions play an important role in oxidative rancidity and development of off-flavor in cooked sardine meat, while TAG fraction plays a minor role in the oxidative deterioration of the meat. Changes in peroxide and thiobarbituric acid values were also monitored. Added EDTA was not effective in controlling the decomposition of lipid hydroperoxide throughout the storage period. However, a combination of NaNO2 and ascorbate not only suppressed the formation but also the decomposition of the primary oxidation products. 相似文献
140.
Nobuko Onozawa-Komatsuzaki Masatoshi Yanagida Takashi Funaki Kazuyuki Kasuga Kazuhiro Sayama Hideki Sugihara 《Inorganic chemistry communications》2009,12(12):1212-1215
A new ruthenium(II)–polypyridine complex (1) having a 2,6-bis(4-carboxyquinolin-2-yl)pyridine ligand was synthesized as a sensitizer for dye-sensitized solar cells (DSCs). This complex exhibited remarkable light-harvesting properties in the near-IR region. DSCs sensitized with 1 showed a 35% incident photon-to-current conversion efficiency (IPCE) at 900 nm. 相似文献